In a conventional direct-mode communication system, coordination must be carried out by a backhaul core network firstly in order to create a communication connection between client direct-mode communication apparatuses. Then, the communication connection can be created between the client direct-mode communication apparatuses for direct message transmission. In this way, data exchange can be accomplished more simply and quickly.
However, creation of the communication connection between the client direct-mode communication apparatuses may require use of an additional connection module and an additional communication protocol. This makes the hardware design more complex or makes the existing hardware of the communication apparatuses unable to support this.
Accordingly, an urgent need exists in the art to provide a solution that can create a communication connection between client direct-mode communication apparatuses more efficiently through use of the existing hardware modules but through adjustment of the communication protocol so as to increase the flexibility in use of the direct-mode communication system.